Plasma addressed display device with a function of controlling partial pressure of dopant gas

Abstract

Object: The object of the invention is to provide a plasma addressed display device which can adapt the amount of dopant gas released or absorbed by the storage material to a changing real-operating/environment conditions of the display device in order to control the partial pressure of the dopant gas in the channel. Configuration: A plasma addressed display device comprising: a channel substrate (2) provided with an array of interconnected longitudinal channel chambers; a cover sheet (4) extending over the channel chambers (30) and making seals to the channel chambers on a side of an upper face of the chamber, whereby the channel substrate and the cover sheet define sealed channel chambers; a pair of electrodes (3a,3c) located in each sealed channel chamber for selectively ionizing a gas within the channel chamber; a dopant source (53) having a storage material that reversibly absorbs and releases a dopant gas to be mixed with a primary ionizable gas in the sealed channel chambers; and a heater (5H) for heating the storage material. The device is provided with a feedback loop (100-103, 5H) for a control of partial pressure of the dopant gas within the sealed channel chambers, the feedback loop comprising: measurement means (100,101) for measuring a value of a decay time of an electrical conductivity in at least one of the channel chambers from turning off the plasma in the channel chamber; and control means (102, 103) for controlling a temperature of the storage material through the heater on the basis of the measured value so that the decay time is within a predetermined range.

Dependencies are inferred from the claim text.